<template>
  <div class="login">
    <div class="box">
      <i class="el-icon-close" @click="close_login"></i>
      <div class="content">
        <div class="nav">
                    <span :class="{active: login_method === 'is_pwd'}"
                          @click="change_login_method('is_pwd')">密码登录</span>
          <span :class="{active: login_method === 'is_sms'}"
                @click="change_login_method('is_sms')">短信登录</span>
        </div>
        <el-form v-if="login_method === 'is_pwd'">
          <el-input
              placeholder="用户名/手机号/邮箱"
              prefix-icon="el-icon-user"
              v-model="username"
              clearable>
          </el-input>
          <el-input
              placeholder="密码"
              prefix-icon="el-icon-key"
              v-model="password"
              clearable
              show-password>
          </el-input>
          <!-- v-model: 实现数据双向绑定，自动将数据绑定给username password-->
          <el-button type="primary" @click="login_password">登录</el-button>
          <span v-for="item in error_message" style="color: red;">{{ item }}</span>
        </el-form>
        <el-form v-if="login_method === 'is_sms'">
          <el-input
              placeholder="手机号"
              prefix-icon="el-icon-phone-outline"
              v-model="mobile"
              clearable
              @blur="check_mobile">  <!--失去焦点事件-->
          </el-input>
          <el-input
              placeholder="验证码"
              prefix-icon="el-icon-chat-line-round"
              v-model="sms"
              clearable>
            <template slot="append">
              <span class="sms" @click="send_sms">{{ sms_interval }}</span>
            </template>
          </el-input>
          <el-button type="primary" @click="login_code">登录</el-button>
        </el-form>
        <div class="foot">
          <span @click="go_register">立即注册</span>
        </div>
      </div>
    </div>
  </div>
</template>

<script>
export default {
  name: "Login",
  data() {
    return {
      username: '',
      password: '',
      mobile: '',
      sms: '',
      login_method: 'is_pwd',
      sms_interval: '获取验证码',
      is_send: false,
      error_message: ''
    }
  },
  methods: {
    close_login() {
      // 向父组件传递信号，在父组件中执行事件
      this.$emit('close')
    },
    go_register() {
      // 向父组件传递信号，在父组件中执行事件
      this.$emit('go')
    },
    change_login_method(method) {
      this.login_method = method;
    },
    check_mobile() {
      if (!this.mobile) return;
      if (!this.mobile.match(/^1[3-9][0-9]{9}$/)) {
        // element-ui的弹窗事件
        this.$message({
          message: '手机号有误',
          type: 'warning',
          duration: 1000,
          onClose: () => {
            this.mobile = '';
          }
        });
        return false;
      }
      // 校验通过，发送axios请求  // `/user/check_telephone/?telephone=${this.mobile}`
      this.$axios.get(this.$settings.base_url + '/user/check_telephone/', {params: {telephone: this.mobile}}).then(response => {
        if (response.data.code === 100) {
          // 手脚号存在
          this.is_send = true;  // 允许发送验证码
        } else {
          // 提示手机号不存在，并清空手机号
          this.$message({
            message: '手机号不存在',
            type: 'warning',
            duration: 1000,
            onClose: () => {
              this.mobile = '';
            }
          });
        }

      }).catch(error => {
        console.log(error)
      })
    },

    send_sms() {

      if (!this.is_send) return;
      this.is_send = false;  // 保证接口幂等性，接口幂等性就是用户对于同一操作发起的一次请求或者多次请求的结果是一致的，不会因为多次点击而产生了副作用
      let sms_interval_time = 60;
      this.sms_interval = "发送中...";

      this.$axios.get(this.$settings.base_url + '/user/send/', {params: {telephone: this.mobile}}).then(response => {
        // 提示验证码发送成功
        if (response.data.code === 100) {
          this.$message({
            message: '验证码发送成功',
            type: 'success',
            duration: 1000,
          });
        }
      }).catch(error => {
        console.log(error)
      })

      // 定时器，每隔1秒将数字减一。
      let timer = setInterval(() => {
        if (sms_interval_time <= 1) {
          clearInterval(timer);
          this.sms_interval = "获取验证码";
          this.is_send = true; // 重新回复点击发送功能的条件
        } else {
          sms_interval_time -= 1;
          this.sms_interval = `${sms_interval_time}秒后再发`;
        }
      }, 1000);
    },

    login_password() {
      if (this.password && this.password) {
        // 发送请求
        this.$axios.post(this.$settings.base_url + "/user/login/",
            {username: this.username, password: this.password}).then(response => {
          // this.$cookies.set(key, value, expire_time)  设置cook
          // this.$cookies.remove(key)  移除cookie
          // this.$cookies.get(key)  获取cookie
          let response_data = response.data
          if (response_data.code === 101) {
            this.error_message = response_data.result.non_field_errors
          } else {
            this.$cookies.set("token", response_data.result.token, '7d')
            this.$cookies.set("username", response_data.result.username, '7d')
            // 子组件向父组件传递时间
            this.$emit('close') // 关闭窗口
            this.$emit('login_success')  // 从cookie中获取username和token
          }
        }).catch(error => {
          // 后端逻辑错误，跳转到404页面
          this.$router.push('/404')
        })
      } else {

        this.$message({
          message: "用户名或密码必须填",
          type: "warning",
        })

      }
    },

    login_code() {
      if (this.mobile && this.sms) {
        // 发送请求
        this.$axios.post(this.$settings.base_url + "/user/telephone_login/",
            {telephone: this.mobile, code: this.sms}).then(response => {
          // this.$cookies.set(key, value, expire_time)  设置cook
          // this.$cookies.remove(key)  移除cookie
          // this.$cookies.get(key)  获取cookie
          let response_data = response.data
          if (response_data.code === 101) {
            this.error_message = response_data.result.non_field_errors
          } else {
            this.$cookies.set("token", response_data.result.token, '7d')
            this.$cookies.set("username", response_data.result.username, '7d')
            // 子组件向父组件传递时间
            this.$emit('close') // 关闭窗口
            this.$emit('login_success')  // 从cookie中获取username和token
          }
        }).catch(error => {
          // 后端逻辑错误，跳转到404页面
          this.$router.push('/404')
        })
      } else {

        this.$message({
          message: "验证码和手机号必须填写",
          type: "warning",
        })

      }
    },

  }
}
</script>

<style scoped>
.login {
  width: 100vw;
  height: 100vh;
  position: fixed;
  top: 0;
  left: 0;
  z-index: 10;
  background-color: rgba(0, 0, 0, 0.3);
}

.box {
  width: 400px;
  height: 420px;
  background-color: white;
  border-radius: 10px;
  position: relative;
  top: calc(50vh - 210px);
  left: calc(50vw - 200px);
}

.el-icon-close {
  position: absolute;
  font-weight: bold;
  font-size: 20px;
  top: 10px;
  right: 10px;
  cursor: pointer;
}

.el-icon-close:hover {
  color: darkred;
}

.content {
  position: absolute;
  top: 40px;
  width: 280px;
  left: 60px;
}

.nav {
  font-size: 20px;
  height: 38px;
  border-bottom: 2px solid darkgrey;
}

.nav > span {
  margin: 0 20px 0 35px;
  color: darkgrey;
  user-select: none;
  cursor: pointer;
  padding-bottom: 10px;
  border-bottom: 2px solid darkgrey;
}

.nav > span.active {
  color: black;
  border-bottom: 3px solid black;
  padding-bottom: 9px;
}

.el-input, .el-button {
  margin-top: 40px;
}

.el-button {
  width: 100%;
  font-size: 18px;
}

.foot > span {
  float: right;
  margin-top: 20px;
  color: orange;
  cursor: pointer;
}

.sms {
  color: orange;
  cursor: pointer;
  display: inline-block;
  width: 70px;
  text-align: center;
  user-select: none;
}
</style>